<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
</head>
<body>
<div id="test">1111</div>
<div id="test2">222</div>
<div class="test3 test4">3344555</div>
<style>
  [id]{
    color: red;
  }
  [id='test']{
    color: red;
    font-size: 30px;
  }
  [class]{
    color: blue;
  }
  [class~='test4']{
    font-size: 40px;
  }
</style>
</body>
</html>
